http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52942
Paolo Carlini <paolo.carlini at oracle dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |NEW Last reconfirmed| |2012-04-12 CC| |jwakely.gcc at gmail dot | |com Ever Confirmed|0 |1 --- Comment #1 from Paolo Carlini <paolo.carlini at oracle dot com> 2012-04-12 01:17:46 UTC --- Your specialization of std::hash doesn't provide the two nested types result_type and argument_type, which are mandatory, per 20.8.12. But another hash function meeting the Hash requirements, which do not mention the nested types should be Ok, and looks like isn't. At the moment I completely fail to see where we are incorrectly assuming the nested types (and, grrrr, the error message doesn't help us much) Jon can you see anything?